By way of brief background, conventional subscriber steering methods are rudimentary and are built on DNS query and response methods that predate the existence of a mobility packet core. An improved method of steering newly arriving sessions based upon intelligent feedback from the network infrastructure is a necessity for future mobility growth.
When subscribers attach to the network for a data service under conventional systems, a query and response DNS system called APN DNS is in place to direct subscribers to the appropriate network device(s). APNs are application environments that expose subscribers to resources like internet access, an enterprise network, voice over long term evolution (VoLTE) service or other mobility application(s). While APN DNS does perform some simple functions, it generally lacks application-level awareness or intelligence that differentiates the responses to a client attempting to locate a service. APN DNS is typically unaware if congestion is occurring on the network, if an end-to-end service is unavailable, if subscribers are being properly rated, or if the arrival of subscribers will exceed the expected capacity of the candidate targets.
Further, APN DNS can be a cumbersome method of managing candidate targets for new subscriber arrivals. APN DNS generally cannot be used during maintenance activities to remove targets to prevent subscriber attaches. The current method of altering APN DNS entries involves loading, editing and distribution of large files that can take hours and reduce maintenance windows within operations. DNS, because of design, is inherently unaware of the application level readiness for the service to which it responds. This results in the current APN DNS being subject to steering clients to impaired or congested environments because feedback is not received from the network regarding the state of the network or elements comprising the network. As such, newly arriving subscribers can be directed to down networks, impaired networks, or systems that are failing to respond.
Moreover, in modern networks, not all environments serving a subscriber are the same in size or licensed capacity. Conventional DNS typically treats environments as having the same capacity. As a result, conventional DNS will typically round-robin load distribute newly arriving subscribers against all designated target environments and, should they be dissimilar in size, this action may have undesirable consequences, as smaller environments may be overrun or may exhaust subscriber-licensed capacity. Virtualization further compounds these problems because subscriber capacity in a packet core can change dynamically as additional virtualized elements can change quickly in an automated fashion. The dynamic nature of a modern virtualized packet core exacerbates the problems introduced by traditional APN DNS behavior and the limited capabilities associated therewith.